ChangeLog for PCRE
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Version 2.00 24-Sep-98
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1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
it any more.
2. Allow quantification of (?>) groups, and make it work correctly.
3. The first character computation wasn't working for (?>) groups.
4. Correct the implementation of \Z (it is permitted to match on the \n at the
end of the subject) and add 5.005's \z, which really does match only at the
very end of the subject.
5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
localized options. All options to pcre_study() were also removed.
7. Add other new features from 5.005:
$(?<= positive lookbehind
$(?a*))*/ (a PCRE_EXTRA facility).
Version 1.00 18-Nov-97
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1. Added compile-time macros to support systems such as SunOS4 which don't have
memmove() or strerror() but have other things that can be used instead.
2. Arranged that "make clean" removes the executables.
Version 0.99 27-Oct-97
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1. Fixed bug in code for optimizing classes with only one character. It was
initializing a 32-byte map regardless, which could cause it to run off the end
of the memory it had got.
2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
Version 0.98 22-Oct-97
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1. Fixed bug in code for handling temporary memory usage when there are more
back references than supplied space in the ovector. This could cause segfaults.
Version 0.97 21-Oct-97
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1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
2. Optimized negated single characters not to use a bit map.
3. Brought error texts together as macro definitions; clarified some of them;
fixed one that was wrong - it said "range out of order" when it meant "invalid
escape sequence".
4. Changed some char * arguments to const char *.
5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
pcretest.
Version 0.96 16-Oct-97
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1. Added a simple "pgrep" utility to the distribution.
2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
where "ddd" means "one or more decimal digits".
3. Fixed serious bug. If a pattern had a back reference, but the call to
pcre_exec() didn't supply a large enough ovector to record the related
identifying subpattern, the match always failed. PCRE now remembers the number
of the largest back reference, and gets some temporary memory in which to save
the offsets during matching if necessary, in order to ensure that
backreferences always work.
4. Increased the compatibility with Perl in a number of ways:
(a) . no longer matches \n by default; an option PCRE_DOTALL is provided
to request this handling. The option can be set at compile or exec time.
(b) $ matches before a terminating newline by default; an option
PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
mode). The option can be set at compile or exec time.
(c) The handling of \ followed by a digit other than 0 is now supposed to be
the same as Perl's. If the decimal number it represents is less than 10
or there aren't that many previous left capturing parentheses, an octal
escape is read. Inside a character class, it's always an octal escape,
even if it is a single digit.
(d) An escaped but undefined alphabetic character is taken as a literal,
unless PCRE_EXTRA is set. Currently this just reserves the remaining
escapes.
(e) {0} is now permitted. (The previous item is removed from the compiled
pattern).
5. Changed all the names of code files so that the basic parts are no longer
than 10 characters, and abolished the teeny "globals.c" file.
6. Changed the handling of character classes; they are now done with a 32-byte
bit map always.
7. Added the -d and /D options to pcretest to make it possible to look at the
internals of compilation without having to recompile pcre.
Version 0.95 23-Sep-97
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1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
\x20 at the start of a run of normal characters. These were being treated as
real characters, instead of the source characters being re-checked.
Version 0.94 18-Sep-97
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1. The functions are now thread-safe, with the caveat that the global variables
containing pointers to malloc() and free() or alternative functions are the
same for all threads.
2. Get pcre_study() to generate a bitmap of initial characters for non-
anchored patterns when this is possible, and use it if passed to pcre_exec().
Version 0.93 15-Sep-97
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1. /(b)|(:+)/ was computing an incorrect first character.
2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
but not actually doing anything yet.
3. Treat "-" characters in classes that cannot be part of ranges as literals,
as Perl does (e.g. [-az] or [az-]).
4. Set the anchored flag if a branch starts with .* or .*? because that tests
all possible positions.
5. Split up into different modules to avoid including unneeded functions in a
compiled binary. However, compile and exec are still in one module. The "study"
function is split off.
6. The character tables are now in a separate module whose source is generated
by an auxiliary program - but can then be edited by hand if required. There are
now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
toupper() in the code.
7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
make them global. Abolish the function for setting them, as the caller can now
set them directly.
Version 0.92 11-Sep-97
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1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
(e.g. /a{1,3}/) was broken (I mis-optimized it).
2. Caseless matching was not working in character classes if the characters in
the pattern were in upper case.
3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
4. Make PCRE_ANCHORED public and accept as a compile option.
5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
pass them.
6. Give an error if bad option bits passed at compile or run time.
7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
pcretest to cause it to pass that flag.
8. Add pcre_info(), to get the number of identifying subpatterns, the stored
options, and the first character, if set.
9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
Version 0.91 10-Sep-97
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1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
match the empty string as in /(a*)*/. It was looping and ultimately crashing.
2. PCRE was looping on encountering an indefinitely repeated back reference to
a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
Perl does - treats the match as successful.
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